Type CNAS and CNFS Freewheels are light duty Roller Ramp Clutches manufactured to standard bearing dimensions; type CNAS to 62 series ball bearings, and type CNFS to NU 23 series roller bearings.
CNAS Clutches
On type CNAS clutches torque transmission from the outer race is by interference fit with the housing bore which needs to be to H6 or J7 tolerance. The housing should be in Steel or high grade cast iron with minimum outside diameter to dimension 'K' in the table. Transmission from shaft is by a key with recommended shaft tolerance h6 or j6, except for clutch CNAS 6 where transmission is by press-fit onto shaft with n6 tolerance.
CNFS Clutches
On type CNFS torque transmission from the outer race is via two keys in the end face of the outer race. For good location of the clutch the housing bore should be to H6 or G7 tolerance, except where keys are not used for the torque transmission , when the housing bore must be to K6 tolerance to provide the necessary interference fit. Transmission from shaft is by a key with recommended shaft tolerance h6 or j6.